This invention relates to a rear view mirror assembly for a vehicle, and more particularly to a support arm for a vehicle mirror assembly, especially commercial vehicles.
Heretofore, vehicle mirrors have been provided which encompass at least one mirror head having at least one mirror pane. This mirror pane can be installed in a mirror housing to be either fixed or adjustable or it can be secured directly in a frame. Furthermore, if need be, an adjusting mechanism to adjust the mirror pane relative to the housing, as opposed to the entire housing, can be included. In a simplified variant, the mirror housing is fastened to an essentially U-shaped metal tube bracket whose two ends are then fastened to bearing blocks mounted to the vehicle. For example, in EP 0 090 909 A3, the adjusting mechanism is fixed to the tube bracket by clamping. In the EP 0 590 510 B1, the housing itself is attached to the tube bracket by clamping. The tubing can then be secured to the bearing blocks mounted to the vehicle. In addition, EP 0 697 311 B1 suggests fastening plastic bearing blocks to the metal tube bracket using a tooth/detent arrangement to enable an angular adjustment of the tube bracket. Although this design is very stable and simple, it has several disadvantages. First, the mirror pane is installed with friction. Secondly, the design is aerodynamically disadvantageous and increases the unfavorable effects of drive resistance and strain resulting from the force of the wind. In addition, the tube bracket, which is completely metal for stability reasons, is also heavy. With the additional plastic bearing blocks, a multitude of individual parts are necessary. This makes the manufacture and the assembly complex and expensive. For this EP 1 024 051 A3 suggests a one-piece support arm with two holding arms and one connection piece connected between the holding arms. The mirror carrier plate can be fixed to the connection piece of the support arm (which is manufactured entirely of plastic) by means of complementary fixing assemblys. This design also has several disadvantages. The mirror housings that were designed for the above-described tube bracket versions cannot be fastened to the support arm requiring several housings to be on hand. Also, in the event of an “upgrade” to a plastic support arm (which is more aerodynamically favorable and lighter), the housing can no longer be used. On the other hand, mirror panes with frames cannot simply be attached to the support arm without a housing. Furthermore, the attachment of the support arm, which is completely manufactured of plastic, is reduced which leaves the attached mirror exposed to vibrations that are wind induced or transferred by the vehicle. A corresponding fastener is necessary for a stable attachment of the housing to the connection piece so that it is not possible by simple turning to use the same support arm for right-hand and left-hand driven vehicles as is the case with the above described tube bracket version, for example. In the driving direction, the driver's mirror is the left external mirror in left-hand driven vehicles and thus is turned around the vertical axis of the vehicle then the passenger side right-hand mirror. In the case of right-hand driven vehicles, this is exactly the opposite. Therefore, up to now it has been necessary to provide four variants, i.e. driver/passenger vehicle for right/left-hand driven.
Accordingly, an object of the present invention is to provide a support arm for a vehicle mirror that has a greater stability and reduced vibrations.
Another object is to provide a support arm for a vehicle mirror that can be used for both driver and passenger mirrors for both right and left-hand driven vehicles.